Scientists in Finland discovered a way to forge short chains of gold nanoparticles with unparalleled precision. The cores of these well-defined nanostructures are composed of just a few hundred metal atoms. But this jewelry won’t be used for fashion. Researchers say the nanogold chains are ideal for the study of interactions between light and matter in metallic nanostructures. They can also be used to analyze surface plasmons, delocalized electrons that oscillate on the interface between two different materials.